The three women were accused of sending threatening emails and making “false and fraudulent” claims of being gang members, according to the Los Angeles County District Attorney’s office.
A fourth woman, a former waitress, also allegedly threatened to harm herself and others.
The women had allegedly sent the emails to people they knew in the restaurant.
One of the women, LaMia Garcia, is also accused of threatening to hurt her family, the Los Angelenos Times reported.
LaMias alleged that one of the letters was a hoax, but authorities have not publicly released the name of the woman.
The three were arrested on Friday in Santa Monica, where LaMieres home is located.
The others are: Lisa Sanchez, 34, of San Diego; Maria Diaz, 40, of Anaheim; and Lisa Guerrero, 28, of Huntington Beach.